Is it possible to control the dimensions of montages from the command line? I'd like to make montages that are the dimensions of my laptop (1600x900) but haven't seen documentation that describes this.

I think if you start off with a canvas of the size you want, that should be all that's required.
I haven't worked with this filter yet, so I could be incorrect about this.

Yes, you can control the dimensions if you assemble the montage within the GIMP program. I should have mentioned that I'm working from the command line. I use this command:

gmic *jpg -gimp_montage 4,\""V(H(0,1),H(2,V(3,4)))"\",1,1.0,0,5,0,0,0,255,0,0,0,0,0 -o output."$(date)".jpg

So I guess I'm looking for a Gimp command to create a canvas of a certain size, and then use the G'mic command in conjunction with it.

I tried the following command with the gimp-canvas filter:

gmic *jpg -gimp_canvas 1600x900 -gimp_montage 4,\""V(H(0,1),H(2,V(3,4)))"\",1,1.0,0,5,0,0,0,255,0,0,0,0,0 -o output."$(date)".jpg

But it returned the error:

[gmic]-42./ *** Error *** Command '-gimp_canvas': Undefined argument '$4', in expression '$4' (for 1 argument specified).
[gmic] Command '-gimp_canvas' has the following description:

[gmic] Command 'gimp_canvas' has no description (did you mean '-gimp_lava' ?). Try 'gmic -h' for global help.

Sorry Serche, but I haven't used the command line for anything as of yet. So I really can't give you any suggestions on it's use or a command that might work.

Only ones I can see is to make it vertical or horizontal. Scaled or aligned. You may be able in the custom field.
If it is too big you may have to scale it still

If no one answers your question here try asking it at this link https://discuss.pixls.us/

Okay thanks! It may not be possible to do what I want. I will check out the link.

Yeah, I get this error too. Any one figured out a way to make this work?

If you want to do the montage for you screen dimensions....since I don't know how to do custom I would .. 1. get all pictures that you want. 2. ask for it to be horizontally arrayed (assuming your screen is horizontal) make sure it is larger than your screen, then scale it to size. You could even do it a little smaller and stretch to screen if you are using as a desktop picture.
Just looking at it again. In
Auto montage the Estimated size is 100% x 100%
custom montage is 150% x 175%
Merging mode - Aligned is 200% x 300%
Scaled is smaller
This is without padding, borders or angles of pictures.

See if you find an answer here. If not you may have to wait for some professional help.
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